Nik van Larebeke - Academia.edu (original) (raw)
Papers by Nik van Larebeke
The scale and scope of the cancer problem in the United States today is much greater than four de... more The scale and scope of the cancer problem in the United States today is much greater than four decades ago when the formal war against the disease was first announced. Patterns of the disease are not fully explained by known risk factors. Much progress has been made in understanding the molecular basis of carcinogenesis, particularly the near consensus (realization) that
Environment international, 2015
Dioxins, PCBs, chlorinated pesticides, brominated flame retardants, bisphenol A, triclosan, perfl... more Dioxins, PCBs, chlorinated pesticides, brominated flame retardants, bisphenol A, triclosan, perfluorinated compounds and phthalates are known as endocrine disrupting chemicals (EDCs). The aim of our study was to investigate whether higher exposure to EDCs is associated with increased subfertility in men. We measured biomarkers of exposure in 163 men, recruited through four fertility clinics. According to WHO guidelines, we used a total motility count (TMC) of 20 million as cut-off value. We assigned patients to the case group when two semen samples - collected at least one week apart - had a TMC<20 and to the control group when both samples had a TMC≥20. To estimate the risk of subfertility and alteration in sex hormone concentrations we used multivariable-adjusted analysis, using logistic and linear regressions, respectively. For an IQR increase in serum oxychlordane, the odds ratio for subfertility was 1.98 (95% CI: 1.07; 3.69). Furthermore, men with serum levels of BDE209 abov...
Carcinogenesis, 2015
Genome instability is a prerequisite for the development of cancer. It occurs when genome mainten... more Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic m...
Environmental Health Perspectives, 2001
In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphen... more In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphenyls (PCBs) and 1 g of dioxins were distributed to animal farms in Belgium, and to a lesser extent in the Netherlands, France, and Germany. This study was based on 20,491 samples collected in the database of the Belgian federal ministries from animal feed, cattle, pork, poultry, eggs, milk, and various fat-containing food items analyzed for their PCB and/or dioxin content. Dioxin measurements showed a clear predominance of polychlorinated dibenzofuran over polychlorinated dibenzodioxin congeners, a dioxin/PCB ratio of approximately 1:50,000 and a PCB fingerprint resembling that of an Aroclor mixture, thus confirming contamination by transformer oil rather than by other environmental sources. In this case the PCBs contribute significantly more to toxic equivalents (TEQ) than dioxins. The respective means ± SDs and the maximum concentrations of dioxin (expressed in TEQ) and PCB observed per gram of fat in contaminated food were 170.3 ± 487.7 pg, 2613.4 pg, 240.7 ± 2036.9 ng, and 51059.0 ng in chicken; 1.9 ± 0.8 pg, 4.3 pg, 34.2 ± 30.5 ng, and 314.0 ng in milk; and 32.0 ± 104.4 pg, 713.3 pg, 392.7 ± 2883.5 ng, and 46000.0 ng in eggs. Assuming that as a consequence of this incident between 10 and 15 kg PCBs and from 200 to 300 mg dioxins were ingested by 10 million Belgians, the mean intake per kilogram of body weight is calculated to maximally 25,000 ng PCBs and 500 pg international TEQ dioxins. Estimates of the total number of cancers resulting from this incident range between 40 and 8,000. Neurotoxic and behavioral effects in neonates are also to be expected but cannot be quantified. Because food items differed widely (more than 50-fold) in the ratio of PCBs to dioxins, other significant sources of contamination and a high background contamination are likely to contribute substantially to the exposure of the Belgian population. Key words: Belgium, cancer, dioxin, food chain, polychlorinated biphenyls, risk assessment. Environ Health Perspect 109:265-273 (2001). [Online 1 March 2001] http://ehpnet1.niehs.nih.gov/docs/2001/109p265-273vanlarebeke/abstract.html
Biomedicine & Pharmacotherapy, 2007
The scale and scope of the cancer problem in the United States today is much greater than four de... more The scale and scope of the cancer problem in the United States today is much greater than four decades ago when the formal war against the disease was first announced. Patterns of the disease are not fully explained by known risk factors. Much progress has been made in understanding the molecular basis of carcinogenesis, particularly the near consensus (realization) that virtually all cancers arise from an accumulation of genetic mutations and the more recent recognition of the role of inflammation and the tissue microenvironment, in particular for hormonedependant cancers. However, most genetic mutations that contribute to cancer are not inherited, and thus must be attributable to accumulation of somatic mutations and epigenetic changes, from as yet poorly understood environmental factors, that certainly cannot be explained entirely by tobacco, use and arise over the course of a lifetime. Much of the national effort to control cancer has focused on detecting and treating the diseasednot on seeking approaches to prevent cases from arising. Given this reality, we present a cross-disciplinary framework for establishing comprehensive research and policy centers focused on environmental oncology to be based at selected academic cancer centers across the country. The principal goal of such centers is to improve the ability to prevent cancer, by developing effective interventions based on insights obtained from epidemiology, including molecular epidemiology and basic scientific research on genomic, metabolomic, and other biomarkers of exposure, susceptibility, and disease. As the needed scientific evidence for environmental factors contributing to cancer is revealed, these academic centers will develop specific interventions and/or policy recommendations regarding ways to lower the burden of cancer, based on existing information about cancer hazards in the personal, occupational, and general environment. Ultimately the centers will improve the ability to identify and control the underlying causes of the occurrence of cancer and its progression.
International Journal of Global Environmental Issues, Feb 1, 2008
The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of... more The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of 2001, in Flanders (Belgium). The main purpose of this project, funded by the Flemish government, is to investigate the relationship between environmental pollution and human health. This is done by measuring pollutants and health effects in human beings. Social scientists cooperating with the environmental and health experts proposed to include a questionnaire on risk perception related to environment and health. Taking into account, risk perception is important with regard to risk communication, risk assessment and the management of complex issues such as health and environment. We present the results of our survey of 1,165 mothers of newborn babies, who participated in the first campaign of the biomonitoring. The perception research discussed in this paper can be evaluated as a successful experiment, with potential for further development and use.
Carcinogenesis, 2015
Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but c... more Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effe...
Resource Management, 2004
Chromosomal Alterations, 2007
We conducted a literature study (papers published until September 2004) concerning quantitative a... more We conducted a literature study (papers published until September 2004) concerning quantitative aspects of the formation of DNA adducts and the induction of sister-chromatid exchanges (SCE) and mutations following benzo[a]pyrene (BaP) exposure. Mean adduct levels per dose unit after exposure in vitro were higher in both human (11 studies) and animal (five studies) cells for doses below 5 μM (2.47 and 1.445 adducts per 106 nucleotides per μM, respectively) than for doses of 5 μM and above (0.104 and 0.106 adducts per 106 nucleotides per μM). In vivo in humans BaP adducts (0.054–0.918 adducts per 106 nucleotides per μM) occur in much lower concentrations than endogenous adducts. The total quantity of nine endogenous adducts in human cells in vivo amounts to between 4.97 and 69.05 adducts per 106 nucleotides. Mean SCE levels per dose unit after exposure in vitro were higher in both human and animal cells for doses below 5 μM BaP (1.48 and 13.32 SCEs per cell per μM, respectively) than for doses of 5 μM and above (0.18 and 0.97 SCEs per cell per μM). In human cells in vitro (three studies, all below 5 μM) a non-significant downward trend in mutation frequency per dose unit with increasing dose was reported, and in Chinese hamster ovary cells doses below 5 μM BaP resulted in a higher mean mutation frequency per micromole per litre (in the HGPRT or the XPRT gene) than doses of 5 μM and above (4.30 vs. 0.88 per 105 cells per micromole per litre). Calculations on cancer risk associated with a certain level of BaP adducts and on the relation between environmental exposures and a threshold level for induction of DNA repair are presented.
International Journal of Hygiene and Environmental Health, 2015
In this paper, based on the Flemish biomonitoring programs, we describe the associations between ... more In this paper, based on the Flemish biomonitoring programs, we describe the associations between internal exposure to organochlorine pollutants and to cadmium (measured in 2004-2005 for adults aged 50-65 years) and self-reported health status obtained through a questionnaire in November 2011. Dioxin-like activity in serum showed a significant positive association with risk of cancer for women. After adjustment for confounders and covariates, the odds ratio for an exposure equal to the 90th percentile was 2.4 times higher than for an exposure equal to the 10th percentile. For both men and women dioxin-like activity and serum hexachlorobenzene (HCB) showed a significant positive association with risk of diabetes and of hypertension. Detailed analysis suggested that an increase in BMI might be part of the mechanism through which HCB contributes to diabetes and hypertension. Serum dichlorodiphenyldichloroethylene (p,p -DDE) concentration showed a significant positive association with diabetes and hypertension in men, but not in women. Serum polychlorinated biphenyl (PCB) 118 showed a significant positive association with diabetes in both men and women, and after adjustment for correlated exposures, also with hypertension in men. Urinary cadmium concentrations showed a significant positive association with hypertension. Urinary cadmium concentrations were (in 2004-2005) significantly higher in persons who felt in less than good health (in 2011) than in persons who felt in very good health. After adjustment for correlated exposures (to HCB, p,p -DDE and PCB118) marker PCBs showed a significant negative association with diabetes and hypertension. Serum p,p -DDE showed in men a significant negative association with risk of diseases based on atheromata. Our findings suggest that exposure to pollutants can lead to an important increase in the risk of diseases such as cancer, diabetes and hypertension. Some pollutants may possibly also decrease the risk of some health problems, although this requires confirmation by other approaches.
Environmental Health, 2008
Background: This study intended to investigate whether residence in areas polluted by heavy indus... more Background: This study intended to investigate whether residence in areas polluted by heavy industry, waste incineration, a high density of traffic and housing or intensive use of pesticides, could contribute to the high incidence of cancer observed in Flanders.
Environmental Research, 2014
As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and diff... more As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and different phthalate metabolites were analyzed, for the first time, in the urine of 210 adolescents in Flanders, Belgium. All chemicals had a detection frequency above 90%. For all compounds, except the sum of DEHP, highest levels were detected during spring. Average values for the Flemish adolescents were in an agreement with concentrations found in different international studies, all confirming the ubiquity of BPA and phthalate exposure. There was a significant correlation between BPA and the different phthalate metabolites (r between 0.26 and 0.39; po0.01). Shared sources of exposure to BPA and phthalates, such as food packaging, were suggested to be responsible for this positive correlation. Different determinants of exposure were evaluated in relation to the urinary concentrations of these chemicals. For BPA, a significant association was observed with household income class, smoking and exposure to environmental tobacco smoke. For phthalates, the following significant associations were observed: age (MBzP), educational level of the adolescent (MBzP), equivalent household income (MnBP), use of personal care products (MnBP and MBzP), wall paper in house (MnBP and MBzP) and use of local vegetables (MnBP and MBzP).
Environmental health : a global access science source, Jan 6, 2010
In order to select priority hotspots for environment and health research in Flanders (Belgium), a... more In order to select priority hotspots for environment and health research in Flanders (Belgium), an open procedure was organized. Environment and health hotspots are strong polluting point sources with possible health effects for residents living in the vicinity of the hot spot. The selection procedure was part of the work of the Flemish Centre of Expertise for Environment and Health, which investigates the relation between environmental pollution and human health. The project is funded and steered by the Flemish government.
Polycyclic aromatic hydrocarbons comprise important carcinogens and through their presence in amb... more Polycyclic aromatic hydrocarbons comprise important carcinogens and through their presence in ambient air, in tobacco smoke and in food, they contribute to the induction of cancer in the lung and in several other organs and to the induction of cardiovascular and airway disease. To investigate the dose-effect relationship following exposure to benzo(a)pyrene (BaP), the most extensively studied PAH, we reviewed the literature concerning quantitative in vitro and in vivo data on the formation of DNA adducts and the induction of sister chromatid exchanges (SCE's) and mutations. In vitro experiments on the formation of BaP-DNA-adducts and on the induction of SCE's and mutations show a trend towards relatively higher effects per dose unit at exposures below 5 μM compared to exposures above 5 μM. For instance, exposures below 5 μM induced, in human cells, a mean of 2.47 add./10 6 nucleotides per μM, while above 5 μM a mean of 0.104 add./10 6 nucleotides per μM were observed. BaP adducts were observed in human white blood cells in smokers (0.0177 add./10 6 nucl.), in occupationally exposed workers (0.0057-0.558 add./10 6 nucl.) and also in non-smoking controls (0.0054 add./10 6 nucl.). BaP adducts occur in much lower concentrations than several endogenous adducts like 8-hydroxyguanine and 7-methylguanine (1). The findings are discussed in terms of cancer risk potentially associated with the presence of a certain level of BaP adducts and with regard to a possible higher impact of low intensity exposures in terms of health effects per dose unit.
Journal of Occupational and Environmental Medicine, 1995
Genetic testing of employees is controversial; objections have been raised with regard to privacy... more Genetic testing of employees is controversial; objections have been raised with regard to privacy, right to work, and the relevance of the tests. A study is being conducted on &amp;amp;amp;amp;amp;quot;the ethical, social, and scientific problems related to the application of genetic screening and genetic monitoring for employees in the context of a European approach to health and safety at work.&amp;amp;amp;amp;amp;quot; A conceptual model is proposed of the complex interactions between exposure, acquired and inherited susceptibility, and risk for disease. The validity of tests for determining genotype and phenotype and their relevance for disease must be evaluated critically to provide an objective basis for ethical discussions. The acceptability of such tests is related to a number of issues, which are identified and discussed.
International Journal of Hygiene and Environmental Health, 2014
In the Flemish human biomonitoring programme FLEHS II (2007-2011) trace metals (Cd, Pb, Cr, Ni, C... more In the Flemish human biomonitoring programme FLEHS II (2007-2011) trace metals (Cd, Pb, Cr, Ni, Cu, Mn, Tl, Sb, As and toxic relevant arsenic) were analysed in the blood and urine of adolescents (14-15 years old) in the reference population in Flanders and in areas of important industrial activities: Genk-Zuid and Menen. After adjustment of the results for confounding factors, the adolescents living in Genk-Zuid had higher levels of Cr, Cu and Tl in blood, higher levels of Cd and toxic relevant arsenic (TRA) in urine, but lower levels of Ni in blood and Sb in urine compared to the reference population. In Menen higher levels of Cd and Cu in urine, higher concentrations of Tl in blood but lower concentrations of Pb in blood and lower Ni, Sb and As in urine were found compared to the reference population. For both the reference population and the hot spots the concentrations are within the ranges found in other countries. Compared to the previous biomonitoring programme FLEHS I (2002-2006) a decrease in the concentrations of Cd and especially of Pb in blood was observed. However, it cannot be excluded that differences between the two campaigns are partially due to different sampling strategies.
International Journal of Global Environmental Issues, 2008
The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of... more The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of 2001, in Flanders (Belgium). The main purpose of this project, funded by the Flemish government, is to investigate the relationship between environmental pollution and human health. This is done by measuring pollutants and health effects in human beings. Social scientists cooperating with the environmental and health experts proposed to include a questionnaire on risk perception related to environment and health. Taking into account, risk perception is important with regard to risk communication, risk assessment and the management of complex issues such as health and environment. We present the results of our survey of 1,165 mothers of newborn babies, who participated in the first campaign of the biomonitoring. The perception research discussed in this paper can be evaluated as a successful experiment, with potential for further development and use.
Environmental Policy and Governance, 2009
Key challenges in the fi eld of environment and health are the interpretation of research data an... more Key challenges in the fi eld of environment and health are the interpretation of research data and the translation into policy measures. We present work of the Flemish Centre of Expertise for Environment and Health, working directly for the Flemish government. The centre investigated the complex relation between environmental pollution and human health by measuring pollutants and health effects in (over 4000) Flemish inhabitants, and developed an action plan for the interpretation of these human biomonitoring results for policy-making. In 2007 the fi rst step of this action plan, the prioritization of research results, was analysed and discussed. We present results of this experience in practice. Copyright
The scale and scope of the cancer problem in the United States today is much greater than four de... more The scale and scope of the cancer problem in the United States today is much greater than four decades ago when the formal war against the disease was first announced. Patterns of the disease are not fully explained by known risk factors. Much progress has been made in understanding the molecular basis of carcinogenesis, particularly the near consensus (realization) that
Environment international, 2015
Dioxins, PCBs, chlorinated pesticides, brominated flame retardants, bisphenol A, triclosan, perfl... more Dioxins, PCBs, chlorinated pesticides, brominated flame retardants, bisphenol A, triclosan, perfluorinated compounds and phthalates are known as endocrine disrupting chemicals (EDCs). The aim of our study was to investigate whether higher exposure to EDCs is associated with increased subfertility in men. We measured biomarkers of exposure in 163 men, recruited through four fertility clinics. According to WHO guidelines, we used a total motility count (TMC) of 20 million as cut-off value. We assigned patients to the case group when two semen samples - collected at least one week apart - had a TMC<20 and to the control group when both samples had a TMC≥20. To estimate the risk of subfertility and alteration in sex hormone concentrations we used multivariable-adjusted analysis, using logistic and linear regressions, respectively. For an IQR increase in serum oxychlordane, the odds ratio for subfertility was 1.98 (95% CI: 1.07; 3.69). Furthermore, men with serum levels of BDE209 abov...
Carcinogenesis, 2015
Genome instability is a prerequisite for the development of cancer. It occurs when genome mainten... more Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic m...
Environmental Health Perspectives, 2001
In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphen... more In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphenyls (PCBs) and 1 g of dioxins were distributed to animal farms in Belgium, and to a lesser extent in the Netherlands, France, and Germany. This study was based on 20,491 samples collected in the database of the Belgian federal ministries from animal feed, cattle, pork, poultry, eggs, milk, and various fat-containing food items analyzed for their PCB and/or dioxin content. Dioxin measurements showed a clear predominance of polychlorinated dibenzofuran over polychlorinated dibenzodioxin congeners, a dioxin/PCB ratio of approximately 1:50,000 and a PCB fingerprint resembling that of an Aroclor mixture, thus confirming contamination by transformer oil rather than by other environmental sources. In this case the PCBs contribute significantly more to toxic equivalents (TEQ) than dioxins. The respective means ± SDs and the maximum concentrations of dioxin (expressed in TEQ) and PCB observed per gram of fat in contaminated food were 170.3 ± 487.7 pg, 2613.4 pg, 240.7 ± 2036.9 ng, and 51059.0 ng in chicken; 1.9 ± 0.8 pg, 4.3 pg, 34.2 ± 30.5 ng, and 314.0 ng in milk; and 32.0 ± 104.4 pg, 713.3 pg, 392.7 ± 2883.5 ng, and 46000.0 ng in eggs. Assuming that as a consequence of this incident between 10 and 15 kg PCBs and from 200 to 300 mg dioxins were ingested by 10 million Belgians, the mean intake per kilogram of body weight is calculated to maximally 25,000 ng PCBs and 500 pg international TEQ dioxins. Estimates of the total number of cancers resulting from this incident range between 40 and 8,000. Neurotoxic and behavioral effects in neonates are also to be expected but cannot be quantified. Because food items differed widely (more than 50-fold) in the ratio of PCBs to dioxins, other significant sources of contamination and a high background contamination are likely to contribute substantially to the exposure of the Belgian population. Key words: Belgium, cancer, dioxin, food chain, polychlorinated biphenyls, risk assessment. Environ Health Perspect 109:265-273 (2001). [Online 1 March 2001] http://ehpnet1.niehs.nih.gov/docs/2001/109p265-273vanlarebeke/abstract.html
Biomedicine & Pharmacotherapy, 2007
The scale and scope of the cancer problem in the United States today is much greater than four de... more The scale and scope of the cancer problem in the United States today is much greater than four decades ago when the formal war against the disease was first announced. Patterns of the disease are not fully explained by known risk factors. Much progress has been made in understanding the molecular basis of carcinogenesis, particularly the near consensus (realization) that virtually all cancers arise from an accumulation of genetic mutations and the more recent recognition of the role of inflammation and the tissue microenvironment, in particular for hormonedependant cancers. However, most genetic mutations that contribute to cancer are not inherited, and thus must be attributable to accumulation of somatic mutations and epigenetic changes, from as yet poorly understood environmental factors, that certainly cannot be explained entirely by tobacco, use and arise over the course of a lifetime. Much of the national effort to control cancer has focused on detecting and treating the diseasednot on seeking approaches to prevent cases from arising. Given this reality, we present a cross-disciplinary framework for establishing comprehensive research and policy centers focused on environmental oncology to be based at selected academic cancer centers across the country. The principal goal of such centers is to improve the ability to prevent cancer, by developing effective interventions based on insights obtained from epidemiology, including molecular epidemiology and basic scientific research on genomic, metabolomic, and other biomarkers of exposure, susceptibility, and disease. As the needed scientific evidence for environmental factors contributing to cancer is revealed, these academic centers will develop specific interventions and/or policy recommendations regarding ways to lower the burden of cancer, based on existing information about cancer hazards in the personal, occupational, and general environment. Ultimately the centers will improve the ability to identify and control the underlying causes of the occurrence of cancer and its progression.
International Journal of Global Environmental Issues, Feb 1, 2008
The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of... more The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of 2001, in Flanders (Belgium). The main purpose of this project, funded by the Flemish government, is to investigate the relationship between environmental pollution and human health. This is done by measuring pollutants and health effects in human beings. Social scientists cooperating with the environmental and health experts proposed to include a questionnaire on risk perception related to environment and health. Taking into account, risk perception is important with regard to risk communication, risk assessment and the management of complex issues such as health and environment. We present the results of our survey of 1,165 mothers of newborn babies, who participated in the first campaign of the biomonitoring. The perception research discussed in this paper can be evaluated as a successful experiment, with potential for further development and use.
Carcinogenesis, 2015
Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but c... more Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effe...
Resource Management, 2004
Chromosomal Alterations, 2007
We conducted a literature study (papers published until September 2004) concerning quantitative a... more We conducted a literature study (papers published until September 2004) concerning quantitative aspects of the formation of DNA adducts and the induction of sister-chromatid exchanges (SCE) and mutations following benzo[a]pyrene (BaP) exposure. Mean adduct levels per dose unit after exposure in vitro were higher in both human (11 studies) and animal (five studies) cells for doses below 5 μM (2.47 and 1.445 adducts per 106 nucleotides per μM, respectively) than for doses of 5 μM and above (0.104 and 0.106 adducts per 106 nucleotides per μM). In vivo in humans BaP adducts (0.054–0.918 adducts per 106 nucleotides per μM) occur in much lower concentrations than endogenous adducts. The total quantity of nine endogenous adducts in human cells in vivo amounts to between 4.97 and 69.05 adducts per 106 nucleotides. Mean SCE levels per dose unit after exposure in vitro were higher in both human and animal cells for doses below 5 μM BaP (1.48 and 13.32 SCEs per cell per μM, respectively) than for doses of 5 μM and above (0.18 and 0.97 SCEs per cell per μM). In human cells in vitro (three studies, all below 5 μM) a non-significant downward trend in mutation frequency per dose unit with increasing dose was reported, and in Chinese hamster ovary cells doses below 5 μM BaP resulted in a higher mean mutation frequency per micromole per litre (in the HGPRT or the XPRT gene) than doses of 5 μM and above (4.30 vs. 0.88 per 105 cells per micromole per litre). Calculations on cancer risk associated with a certain level of BaP adducts and on the relation between environmental exposures and a threshold level for induction of DNA repair are presented.
International Journal of Hygiene and Environmental Health, 2015
In this paper, based on the Flemish biomonitoring programs, we describe the associations between ... more In this paper, based on the Flemish biomonitoring programs, we describe the associations between internal exposure to organochlorine pollutants and to cadmium (measured in 2004-2005 for adults aged 50-65 years) and self-reported health status obtained through a questionnaire in November 2011. Dioxin-like activity in serum showed a significant positive association with risk of cancer for women. After adjustment for confounders and covariates, the odds ratio for an exposure equal to the 90th percentile was 2.4 times higher than for an exposure equal to the 10th percentile. For both men and women dioxin-like activity and serum hexachlorobenzene (HCB) showed a significant positive association with risk of diabetes and of hypertension. Detailed analysis suggested that an increase in BMI might be part of the mechanism through which HCB contributes to diabetes and hypertension. Serum dichlorodiphenyldichloroethylene (p,p -DDE) concentration showed a significant positive association with diabetes and hypertension in men, but not in women. Serum polychlorinated biphenyl (PCB) 118 showed a significant positive association with diabetes in both men and women, and after adjustment for correlated exposures, also with hypertension in men. Urinary cadmium concentrations showed a significant positive association with hypertension. Urinary cadmium concentrations were (in 2004-2005) significantly higher in persons who felt in less than good health (in 2011) than in persons who felt in very good health. After adjustment for correlated exposures (to HCB, p,p -DDE and PCB118) marker PCBs showed a significant negative association with diabetes and hypertension. Serum p,p -DDE showed in men a significant negative association with risk of diseases based on atheromata. Our findings suggest that exposure to pollutants can lead to an important increase in the risk of diseases such as cancer, diabetes and hypertension. Some pollutants may possibly also decrease the risk of some health problems, although this requires confirmation by other approaches.
Environmental Health, 2008
Background: This study intended to investigate whether residence in areas polluted by heavy indus... more Background: This study intended to investigate whether residence in areas polluted by heavy industry, waste incineration, a high density of traffic and housing or intensive use of pesticides, could contribute to the high incidence of cancer observed in Flanders.
Environmental Research, 2014
As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and diff... more As part of the second Flemish Environment and Health Study (FLEHS II), bisphenol-A (BPA) and different phthalate metabolites were analyzed, for the first time, in the urine of 210 adolescents in Flanders, Belgium. All chemicals had a detection frequency above 90%. For all compounds, except the sum of DEHP, highest levels were detected during spring. Average values for the Flemish adolescents were in an agreement with concentrations found in different international studies, all confirming the ubiquity of BPA and phthalate exposure. There was a significant correlation between BPA and the different phthalate metabolites (r between 0.26 and 0.39; po0.01). Shared sources of exposure to BPA and phthalates, such as food packaging, were suggested to be responsible for this positive correlation. Different determinants of exposure were evaluated in relation to the urinary concentrations of these chemicals. For BPA, a significant association was observed with household income class, smoking and exposure to environmental tobacco smoke. For phthalates, the following significant associations were observed: age (MBzP), educational level of the adolescent (MBzP), equivalent household income (MnBP), use of personal care products (MnBP and MBzP), wall paper in house (MnBP and MBzP) and use of local vegetables (MnBP and MBzP).
Environmental health : a global access science source, Jan 6, 2010
In order to select priority hotspots for environment and health research in Flanders (Belgium), a... more In order to select priority hotspots for environment and health research in Flanders (Belgium), an open procedure was organized. Environment and health hotspots are strong polluting point sources with possible health effects for residents living in the vicinity of the hot spot. The selection procedure was part of the work of the Flemish Centre of Expertise for Environment and Health, which investigates the relation between environmental pollution and human health. The project is funded and steered by the Flemish government.
Polycyclic aromatic hydrocarbons comprise important carcinogens and through their presence in amb... more Polycyclic aromatic hydrocarbons comprise important carcinogens and through their presence in ambient air, in tobacco smoke and in food, they contribute to the induction of cancer in the lung and in several other organs and to the induction of cardiovascular and airway disease. To investigate the dose-effect relationship following exposure to benzo(a)pyrene (BaP), the most extensively studied PAH, we reviewed the literature concerning quantitative in vitro and in vivo data on the formation of DNA adducts and the induction of sister chromatid exchanges (SCE's) and mutations. In vitro experiments on the formation of BaP-DNA-adducts and on the induction of SCE's and mutations show a trend towards relatively higher effects per dose unit at exposures below 5 μM compared to exposures above 5 μM. For instance, exposures below 5 μM induced, in human cells, a mean of 2.47 add./10 6 nucleotides per μM, while above 5 μM a mean of 0.104 add./10 6 nucleotides per μM were observed. BaP adducts were observed in human white blood cells in smokers (0.0177 add./10 6 nucl.), in occupationally exposed workers (0.0057-0.558 add./10 6 nucl.) and also in non-smoking controls (0.0054 add./10 6 nucl.). BaP adducts occur in much lower concentrations than several endogenous adducts like 8-hydroxyguanine and 7-methylguanine (1). The findings are discussed in terms of cancer risk potentially associated with the presence of a certain level of BaP adducts and with regard to a possible higher impact of low intensity exposures in terms of health effects per dose unit.
Journal of Occupational and Environmental Medicine, 1995
Genetic testing of employees is controversial; objections have been raised with regard to privacy... more Genetic testing of employees is controversial; objections have been raised with regard to privacy, right to work, and the relevance of the tests. A study is being conducted on &amp;amp;amp;amp;amp;quot;the ethical, social, and scientific problems related to the application of genetic screening and genetic monitoring for employees in the context of a European approach to health and safety at work.&amp;amp;amp;amp;amp;quot; A conceptual model is proposed of the complex interactions between exposure, acquired and inherited susceptibility, and risk for disease. The validity of tests for determining genotype and phenotype and their relevance for disease must be evaluated critically to provide an objective basis for ethical discussions. The acceptability of such tests is related to a number of issues, which are identified and discussed.
International Journal of Hygiene and Environmental Health, 2014
In the Flemish human biomonitoring programme FLEHS II (2007-2011) trace metals (Cd, Pb, Cr, Ni, C... more In the Flemish human biomonitoring programme FLEHS II (2007-2011) trace metals (Cd, Pb, Cr, Ni, Cu, Mn, Tl, Sb, As and toxic relevant arsenic) were analysed in the blood and urine of adolescents (14-15 years old) in the reference population in Flanders and in areas of important industrial activities: Genk-Zuid and Menen. After adjustment of the results for confounding factors, the adolescents living in Genk-Zuid had higher levels of Cr, Cu and Tl in blood, higher levels of Cd and toxic relevant arsenic (TRA) in urine, but lower levels of Ni in blood and Sb in urine compared to the reference population. In Menen higher levels of Cd and Cu in urine, higher concentrations of Tl in blood but lower concentrations of Pb in blood and lower Ni, Sb and As in urine were found compared to the reference population. For both the reference population and the hot spots the concentrations are within the ranges found in other countries. Compared to the previous biomonitoring programme FLEHS I (2002-2006) a decrease in the concentrations of Cd and especially of Pb in blood was observed. However, it cannot be excluded that differences between the two campaigns are partially due to different sampling strategies.
International Journal of Global Environmental Issues, 2008
The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of... more The Centre of Expertise for Health and Environment started a biomonitoring campaign at the end of 2001, in Flanders (Belgium). The main purpose of this project, funded by the Flemish government, is to investigate the relationship between environmental pollution and human health. This is done by measuring pollutants and health effects in human beings. Social scientists cooperating with the environmental and health experts proposed to include a questionnaire on risk perception related to environment and health. Taking into account, risk perception is important with regard to risk communication, risk assessment and the management of complex issues such as health and environment. We present the results of our survey of 1,165 mothers of newborn babies, who participated in the first campaign of the biomonitoring. The perception research discussed in this paper can be evaluated as a successful experiment, with potential for further development and use.
Environmental Policy and Governance, 2009
Key challenges in the fi eld of environment and health are the interpretation of research data an... more Key challenges in the fi eld of environment and health are the interpretation of research data and the translation into policy measures. We present work of the Flemish Centre of Expertise for Environment and Health, working directly for the Flemish government. The centre investigated the complex relation between environmental pollution and human health by measuring pollutants and health effects in (over 4000) Flemish inhabitants, and developed an action plan for the interpretation of these human biomonitoring results for policy-making. In 2007 the fi rst step of this action plan, the prioritization of research results, was analysed and discussed. We present results of this experience in practice. Copyright